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991.
Jing Kong Han Zhao Qianhui Shang Zhifei Ma Ni Kang Junling Tan 《Cell communication & adhesion》2018,24(1):11-18
Salivary gland adenoid cystic carcinoma (SACC) is one of the most common malignancies in the oral and maxillofacial region. Carcinoma-associated fibroblast (CAF) is an important component in the tumor microenvironment and participates in SACC progression. In this study, we established a CAF cell line derived from a human SACC and named it CAF-SA. It was identified that CAF-SA expressed typical CAF biomarkers. Then, we studied the cellular communications between CAF-SA, tumor cells and endothelial cells. It was found that CAF-SA promoted the migration, invasion, and proliferation of SACC tumor cells in vitro. In addition, tube formation by endothelial cells was enhanced by CAF-SA. In vivo experiment showed that SACC cells formed larger xenografts in nude mice when they were transplanted with CAF-SA. Overall, we demonstrated that CAF-SA exhibited the most important defining feature of CAF by promoting cancer progression. 相似文献
992.
Wei Hongfei Zhao Genhai Liu Hui Wang Han Ni Wenfeng Wang Peng Zheng Zhiming 《Bioprocess and biosystems engineering》2018,41(1):107-113
Bioprocess and Biosystems Engineering - Menaquinone homologs (MK-n), that is, MK-4, MK-5, and MK-6, can be produced by the fermentation of Flavobacterium. In this study, we proposed a simple and... 相似文献
993.
Hongmei Ke Zhi Feng Min Liu Tianhui Sun Jianli Dai Mengqi Ma Lu-Ping Liu Jian-Quan Ni Jos Carlos Pastor-Pareja 《遗传学报》2018,45(6):299-313
Collagens are large secreted trimeric proteins making up most of the animal extracellular matrix. Secretion of collagen has been a focus of interest for cell biologists in recent years because collagen trimers are too large and rigid to fit into the COPII vesicles mediating transport from the endoplasmic reticulum (ER) to the Golgi. Collagen-specific mechanisms to create enlarged ER-to-Golgi transport carriers have been postulated, including cargo loading by conserved ER exit site (ERES) protein Tango1. Here, we report an RNAi screening for genes involved in collagen secretion in Drosophila. In this screening, we examined distribution of GFP-tagged Collagen IV in live animals and found 88 gene hits for which the knockdown produced intracellular accumulation of Collagen IV in the fat body, the main source of matrix proteins in the larva. Among these hits, only two affected collagen secretion specifically: PH4αEFB and Plod, encoding enzymes known to mediate posttranslational modification of collagen in the ER. Every other intracellular accumulation hit affected general secretion, consistent with the notion that secretion of collagen does not use a specific mode of vesicular transport, but the general secretory pathway. Included in our hits are many known players in the eukaryotic secretory machinery, like COPII and COPI components, SNAREs and Rab-GTPase regulators. Our further analysis of the involvement of Rab-GTPases in secretion shows that Rab1, Rab2 and RabX3, are all required at ERES, each of them differentially affecting ERES morphology. Abolishing activity of all three by Rep knockdown, in contrast, led to uncoupling of ERES and Golgi. We additionally present a characterization of a screening hit we named trabuco (tbc), encoding an ERES-localized TBC domain-containing Rab-GAP. Finally, we discuss the success of our screening in identifying secretory pathway genes in comparison to two previous secretion screenings in Drosophila S2 cells. 相似文献
994.
Bo Jin Huan-Chun Ni Wei Shen Jian Li Hai-Ming Shi Yong Li 《Molecular biology reports》2011,38(3):1697-1702
Patients with lesser degrees of platelet inhibition in response to clopidogrel appear to be at increased risk for recurrent
ischemic events. Cytochrome P450 (CYP) polymorphisms have been proposed as possible mechanisms for nonresponsiveness to clopidogrel.
Published data on the association between CYP2C19*2 polymorphism and atherothrombotic events are inconclusive. To derive a
more precise estimation of the relationship, a meta-analysis was performed. A total of eight prospective cohort studies including
2,345 patients carrying CYP2C19*2 variant allele and 5,935 cases with the wild-type genotype were included in this meta-analysis.
Overall, borderline statistically significantly elevated risk of adverse clinical events was associated with genotyping 681G>A
polymorphism (for AA + GA vs. GG: OR, 1.46; 95% CI, 1.01 to 2.13; P = 0.05). The summary odds ratio showed a significant association between the CYP2C19*2 polymorphism and an increased risk
of cardiac mortality in the follow-up period (OR, 2.07; 95% CI, 1.22 to 3.52; P = 0.007). When studies evaluating myocadial infarction, stent thrombosis, and ischemic stroke, the presence of the variant
allele was associated with significantly increased risks of recurrent atherothrombotic events. In summary, this meta-analysis
indicated that CYP2C19*2 carrier status is significantly associated with an increased risk of adverse cardiovascular events. 相似文献
995.
Qi Xu Demin Cheng Yi Liu Honghong Pan Guanru Li Ping Li Yan Li Wenqing Sun Dongyu Ma Chunhui Ni 《Journal of cellular and molecular medicine》2021,25(15):7294-7306
Dysregulation of non-coding RNAs (ncRNAs) has been proved to play pivotal roles in epithelial-mesenchymal transition (EMT) and fibrosis. We have previously demonstrated the crucial function of long non-coding RNA (lncRNA) ATB in silica-induced pulmonary fibrosis-related EMT progression. However, the underlying molecular mechanism has not been fully elucidated. Here, we verified miR-29b-2-5p and miR-34c-3p as two vital downstream targets of lncRNA-ATB. As opposed to lncRNA-ATB, a significant reduction of both miR-29b-2-5p and miR-34c-3p was observed in lung epithelial cells treated with TGF-β1 and a murine silicosis model. Overexpression miR-29b-2-5p or miR-34c-3p inhibited EMT process and abrogated the pro-fibrotic effects of lncRNA-ATB in vitro. Further, the ectopic expression of miR-29b-2-5p and miR-34c-3p with chemotherapy attenuated silica-induced pulmonary fibrosis in vivo. Mechanistically, TGF-β1-induced lncRNA-ATB accelerated EMT as a sponge of miR-29b-2-5p and miR-34c-3p and shared miRNA response elements with MEKK2 and NOTCH2, thus relieving these two molecules from miRNA-mediated translational repression. Interestingly, the co-transfection of miR-29b-2-5p and miR-34c-3p showed a synergistic suppression effect on EMT in vitro. Furthermore, the co-expression of these two miRNAs by using adeno-associated virus (AAV) better alleviated silica-induced fibrogenesis than single miRNA. Approaches aiming at lncRNA-ATB and its downstream effectors may represent new effective therapeutic strategies in pulmonary fibrosis. 相似文献
996.
目的:建立鼠伤寒沙门氏菌诱导昆明小鼠肠道感染模型。方法:先用5 mg/mL链霉素预处理2 d,提高小鼠对鼠伤寒沙门氏菌的敏感性,然后正常饲养1 d,攻毒前禁水禁食4 h,再分别以不同剂量灌胃攻毒2次,间隔24 h。观察小鼠临床症状,并通过组织病理切片、透射电镜和免疫组织化学的方法,分别观察小鼠肠道组织病理变化、小肠上皮细胞超微结构变化及肠道淋巴细胞增殖状况。结果:攻毒后昆明小鼠会出现昏睡、食欲不振、寒颤,甚至死亡的现象,解剖后发现小鼠肠道充血膨胀。组织病理切片显示小鼠肠粘膜受损,小肠绒毛肿胀,排列杂乱,炎性细胞浸润;透射电镜观察超微结构显示小肠上皮细胞线粒体空泡化,嵴和膜发生融合消失,粗面内质网发生扩张;免疫组织化学的方法显示肠道感染后,淋巴结肿大,T淋巴细胞大量增殖。结论:该模型对探索鼠伤寒沙门氏菌引发肠炎的发病机制、病理生理、免疫等方面作用具有重要意义,并为特异性卵黄抗体被动免疫保护效果的后续评价奠定基础。 相似文献
997.
Rui Wang Jingman Ni Xiaoyu Hu Yaping Ma Xiangqun Li Dingjian Yang Shouliang Dong Xiaowu Yang Xinfu Pan 《中国科学C辑(英文版)》1997,40(5):518-523
The second zinc finger fragment of Sp1 (Sp1-ZF2), its mutant (Sp1-ZF2/HT. E20 → H, R23 → T), and two mimic analogues (ZF20 and ZF15) were synthesized by stepwise solid phase technique. The CD spectra and UV-visible spectrum with CoC12 indicated that the formation of zinc finger structure was affected not only by the hydrophobic amino acids but also by the change of the distance between Cys and His. Gel-retardat ion electrophoresis assays indicated that the Glu and Arg residues are very important for recognition. A single zinc finger like Sp1-ZF2 is able to bind DNA sequence specifically. 相似文献
998.
999.
Chen J Jiang X Jiang W Mei N Gao X Zhang Q 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,805(1):169-173
A high-performance liquid chromatographic (HPLC) method with fluorescence detection has been developed for the determination of rizatriptan in human plasma. Following a single-step liquid-liquid extraction with methyl tertiarybutyl ether, the analytes were separated using a mobile phase consisting of 0.05% (v/v) triethylamine in water (adjusting to pH 2.75 with 85% phosphoric acid) and acetonitrile (92:8, v/v). Fluorescence detection was performed at an excitation wavelength of 225nm and an emission wavelength of 360nm. The linearity for rizatriptan was within the concentration range of 0.5-50ng/ml. The intra- and inter-day precisions of the method were not more than 8.0%. The lower limit of quantification (LLOQ) was 0.5ng/ml for rizatriptan. The method was sensitive, simple and repeatable enough to be used in pharmacokinetic studies. 相似文献
1000.
Min Da Yu Feng Jing Xu Yuanli Hu Yuan Lin Bixian Ni Bo Qian Zhibin Hu Xuming Mo 《PloS one》2014,9(10)
Aminoacyl-tRNA synthetases (ARSs) are in charge of cellular protein synthesis and have additional domains that function in a versatile manner beyond translation. Eight core ARSs (EPRS, MRS, QRS, RRS, IRS, LRS, KRS, DRS) combined with three nonenzymatic components form a complex known as multisynthetase complex (MSC).We hypothesize that the single-nucleotide polymorphisms (SNPs) of the eight core ARS coding genes might influence the susceptibility of sporadic congenital heart disease (CHD). Thus, we conducted a case-control study of 984 CHD cases and 2953 non-CHD controls in the Chinese Han population to evaluate the associations of 16 potentially functional SNPs within the eight ARS coding genes with the risk of CHD. We observed significant associations with the risk of CHD for rs1061248 [G/A; odds ratio (OR) = 0.90, 95% confidence interval (CI) = 0.81–0.99; P = 3.81×10−2], rs2230301 [A/C; OR = 0.73, 95%CI = 0.60–0.90, P = 3.81×10−2], rs1061160 [G/A; OR = 1.18, 95%CI = 1.06–1.31; P = 3.53×10−3] and rs5030754 [G/A; OR = 1.39, 95%CI = 1.11–1.75; P = 4.47×10−3] of EPRS gene. After multiple comparisons, rs1061248 conferred no predisposition to CHD. Additionally, a combined analysis showed a significant dosage-response effect of CHD risk among individuals carrying the different number of risk alleles (P
trend = 5.00×10−4). Compared with individuals with “0–2” risk allele, those carrying “3”, “4” or “5 or more” risk alleles had a 0.97-, 1.25- or 1.38-fold increased risk of CHD, respectively. These findings indicate that genetic variants of the EPRS gene may influence the individual susceptibility to CHD in the Chinese Han population. 相似文献